U.S. patent application number 16/224244 was filed with the patent office on 2020-06-18 for decarboxylation and amidation of polyitaconic acid polymers.
The applicant listed for this patent is Itaconix Corporation. Invention is credited to Yvon DURANT, Melanie HUGHES, Bo JIANG, Timothy MILLS.
Application Number | 20200190235 16/224244 |
Document ID | / |
Family ID | 71073395 |
Filed Date | 2020-06-18 |
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United States Patent
Application |
20200190235 |
Kind Code |
A1 |
DURANT; Yvon ; et
al. |
June 18, 2020 |
DECARBOXYLATION AND AMIDATION OF POLYITACONIC ACID POLYMERS
Abstract
The present invention is directed at the decarboxylation and
amidation of polyitaconic acid polymers. The polymers formed have
useful dispersion properties and are suitable for use in the
prevention of scaling.
Inventors: |
DURANT; Yvon; (Lee, NH)
; JIANG; Bo; (Newmarket, NH) ; HUGHES;
Melanie; (Chester, GB) ; MILLS; Timothy;
(Chester, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Itaconix Corporation |
Stratham |
NH |
US |
|
|
Family ID: |
71073395 |
Appl. No.: |
16/224244 |
Filed: |
December 18, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08F 8/32 20130101; C02F
5/00 20130101; C08G 81/025 20130101; C08F 22/02 20130101; C08F 8/34
20130101; C08F 8/00 20130101; C08F 8/00 20130101; C08F 8/34
20130101; C08F 122/02 20130101; C08F 8/00 20130101; C08F 8/32
20130101; C08F 122/02 20130101 |
International
Class: |
C08F 22/02 20060101
C08F022/02; C08F 8/32 20060101 C08F008/32 |
Claims
1. A method of simultaneously decarboxylating and introducing amide
functionality to a polymer comprising: (a) supplying the following
polymer wherein repeating unit c is optional: ##STR00018## wherein
R.sub.1 and R.sub.1' are independently selected from the group
consisting of an --OH group or O.sup.-M.sup.+ where M=Na, K, Li or
a primary, secondary or tertiary amine; R.sub.2 is selected from
the group consisting of a hydrogen atom, a methyl or ethyl group;
R.sub.3 is selected from the group consisting of a hydrogen atom,
methyl group, ethyl group, aromatic group, acetate group, alcohol
group, carboxylic group, a carboxylate (--COO.sup.-M.sup.+) with
M=Na, K, Li or a primary, secondary or tertiary amine providing the
cationic charge, an amide group, a sulfonic or a phosphonic acid
group, an aromatic group; an alkyl acrylate, an alkyl acetate
group, a nitrile group, a halide group; (b) simultaneously
decarboxylating said polymer and introducing amide functionality to
form: ##STR00019## wherein repeat unit a in the above structure is
present in the range of 1-99 wt. %, repeat unit b is present in the
range of 1-99 wt. % and repeat unit c is present in the range of
0-50 wt. % wherein repeat units a, b and c are present at a total
100 wt. %; wherein R.sub.4, R.sub.5 and R.sub.6 are independently
selected from the group consisting of an --OH group or
O.sup.-M.sup.+ where M=Na, K, Li or a primary, secondary or
tertiary amine and at least a portion of R.sub.4, R.sub.5 and
R.sub.6 is --NHR.sub.7 wherein R.sub.7 in --NHR.sub.7 is
independently selected from the group consisting of: (1) an alkyl
chain of up to and including 20 carbon atoms optionally including a
sulfonic acid group, an alcohol group, amine group or carboxylic
acid group; (2) an L-cysteine derivative comprising: ##STR00020##
or (3) an aromatic group; (4) alkyl polyether functionality; or (5)
polysiloxane functionality.
2. The method of claim 1 wherein said polymer formed in step (b)
has a number average molecular weight of 500 to 10,000.
3. The method of claim 1 wherein said polymer formed in step (b)
has a weight average molecular weight of 800 to 100,000.
4. The method of claim 1 wherein said polymer formed in step (b)
has the following structure: ##STR00021##
5. The method of claim 1 wherein said polymer formed in step (b)
has the following structure: ##STR00022##
6. The method of claim 1 wherein said polymer formed in step (b)
has the following structure: ##STR00023##
7. The method of claim 1 wherein said polymer formed in step (b)
has the following structure: ##STR00024##
8. The method of claim 1 wherein said polymer formed in step (b)
has the following structure: ##STR00025##
9. The method of claim 1 wherein the polymer formed in step (b) has
the following structure: ##STR00026##
10. The method of claim 1 wherein the polymer formed in step (b)
has the following structure: ##STR00027##
11. The method of claim 1 wherein repeat unit repeat unit a is
present at a level of 5-80 wt. %, repeat unit b is present at a
level of 5-80 wt. % and repeat unit c is present at a level of 0-35
wt. %.
12. The method of claim 1 wherein repeat unit a is present at a
value of 5-30 wt. %, repeat unit b is present at a level of 60-80
wt. % and repeat unit c is present at a level of 0-25 wt. %.
Description
FIELD
[0001] The present invention is directed at the decarboxylation and
amidation of polyitaconic acid polymers. The polymers formed have
useful dispersion properties and are suitable for use in the
prevention of scaling.
BACKGROUND
[0002] The polymerization of vinyl type monomers that contain
pendant carboxylic acid functionality has always presented some
unique challenges. For example, U.S. Pat. No. 5,223,592 reports
that the critical aspect is to provide complete neutralization of
an itaconic acid type monomer prior to conducting the
polymerization reaction, where complete neutralization is
identified as having two moles of base neutralizer for each mole of
itaconic acid. U.S. Pat. No. 5,336,744 reports that polymers of
itaconic acid are formed at high conversion by an aqueous
polymerization process of partially neutralized monomer solution,
water, polyvalent metal ion, and initiator.
[0003] U.S. Pat. No. 3,444,143 reports on partially decarboxylated
polymers and copolymers of itaconic acid where up to about 30 mole
percent of carbon dioxide is evolved per molar equivalent of
itaconic acid in the polymer.
[0004] U.S. Pat. No. 9,487,423 reports on the partial
decarboxylation of polyitaconic acid polymers or copolymers. The
partially decarboxylated resins are suitable for use in preparation
of dispersions as well as in anti-scaling applications.
SUMMARY
[0005] A method of simultaneously decarboxylating and introducing
amide functionality to a polymer comprising:
[0006] (a) supplying the following polymer wherein repeating unit c
is optional:
##STR00001##
[0007] wherein R.sub.1 and R.sub.1' are independently selected from
the group consisting of an --OH group or O.sup.-M.sup.+ where M=Na,
K, Li or a primary, secondary or tertiary amine;
[0008] R.sub.2 is selected from the group consisting of a hydrogen
atom, a methyl or ethyl group;
[0009] R.sub.3 is selected from the group consisting of a hydrogen
atom, methyl group, ethyl group, aromatic group, acetate group,
alcohol group, carboxylic group, a carboxylate (--COO.sup.-M.sup.+)
with M=Na, K, Li or a primary, secondary or tertiary amine
providing the cationic charge, an amide group, a phosphonic acid
group, an aromatic group; an alkyl acrylate, an alkyl acetate group
a nitrile group, a halide group;
[0010] (b) simultaneously decarboxylating said polymer and
introducing amide functionality to form:
##STR00002##
[0011] wherein repeat unit a in the above structure is present in
the range of 1-99 wt. %, repeat unit b is present in the range of
1-99 wt. % and repeat unit c is present in the range of 0-50 wt. %
wherein repeat units a, b and c are present at a total 100 wt. %
and wherein R.sub.4, R.sub.5 and R.sub.6 can be independently
selected from the group consisting of an --OH group or
O.sup.-M.sup.+ where M=Na, K, Li or a primary, secondary or
tertiary amine and at least a portion of R.sub.4, R.sub.5 or
R.sub.6 is --NHR.sub.7 wherein R.sub.7 in --NHR.sub.7 is
independently selected from the group consisting of:
[0012] (1) an alkyl chain of up to and including 20 carbon atoms,
to provide for example: --(CH.sub.2).sub.19CH.sub.3, said alkyl
chain optionally including a sulfonic acid group, an alcohol group,
an amine group or carboxylic acid group to provide, for example:
--CH.sub.2CH.sub.2--SO.sub.3H or --CH.sub.2CH.sub.2OH or
--CH.sub.2CH.sub.2NH.sub.2 or --CH.sub.2CH.sub.2COOH;
[0013] (2) an L-cysteine derivative comprising:
##STR00003##
[0014] (3) an aromatic group;
[0015] (4) alkyl polyether functionality; or
[0016] (5) polysiloxane functionality.
[0017] The polymer structures so formed from the simultaneous
decarboxylation and introduction of amide functionality may be used
to form dispersions and/or to provide aqueous systems for
prevention of scaling.
DETAILED DESCRIPTION
[0018] The preferred monomers suitable for polymerization herein
include the general structures below. Accordingly, a first itaconic
acid monomer having the following structure:
##STR00004##
[0019] In addition, the itaconic acid may be present in partially
neutralized form as the metal salt of itaconic acid as in:
##STR00005##
where M.sup.+ is reference to a metal such as Na, K, or Li or a
primary, secondary or tertiary amine providing the cationic charge.
For example, the above carboxylate group may be present as:
##STR00006##
where X may be an alkyl group or an aryl group or hydrogen (e.g.
--NH.sub.4.sup.+).
[0020] It has been found that to provide for relatively more
efficient polymerization and in particular relatively high
conversion (e.g. conversion at or greater than 75% wt of the
monomer) the itaconic acid monomers identified above are preferably
neutralized under selected conditions in order to optimize the
ensuing polymerization which may then improve values of conversion
and/or molecular weight. The molecular weights that are improved
may include the number average molecular weight (Mn) and/or weight
average molecular weight (Mw).
[0021] The amount of neutralization may be adjusted to provide a
less than complete neutralization of the acidic groups present on
the itaconic acid monomers. For example, in the case of itaconic
acid, it may be understood that complete neutralization will
require two moles of neutralizer for each mole of itaconic acid.
That is, two moles of sodium hydroxide would provide complete
neutralization of one mole of itaconic acid, and any amount of
sodium hydroxide less than two moles would provide the desired
result of partial neutralization. Those of skill in the art would
recognize that when a divalent base is employed to neutralize
itaconic acid, the amount of divalent base selected to completely
neutralize itaconic acid would be 1.0 mole of divalent base for
each mole of itaconic acid, and to partially neutralize, less than
one mole of divalent base may be applied to partially neutralize
the itaconic acid monomer.
[0022] It has been found that the level of neutralization herein
may be preferentially maintained at about 25.0 mole % to 85.0 mole
%, including all values therein, in 1.0 mole % increments. For
example, for a 1.0 moles of itaconic acid, one may preferably
neutralize 0.25 moles of the acid groups present to 0.85 moles of
the acid groups present. More preferably, the level of
neutralization may be maintained at a level of 40.0 mole % to 60.0
mole %, and in a most preferred embodiment, the level of
neutralization of the acid monomer selected may be in the range of
45.0 mole % to 55.0 mole %.
[0023] The temperature at which partial neutralization may be
achieved may also be adjusted such that neutralization is
accomplished at temperatures of 50.degree. C. to 150.degree. C.,
including all values therein, in 1.0.degree. C. increments. For
example, it is preferable that the neutralization temperature is
adjusted to be 50.degree. C. to 110.degree. C., and in a most
preferred configuration, the neutralization temperature is adjusted
to be in the range of 65.degree. C. to 100.degree. C.
[0024] A second monomer may optionally be employed herein, of the
following general structure:
##STR00007##
wherein R.sub.2 can be either a hydrogen atom, a methyl or ethyl
group and R.sub.3 is either a hydrogen atom, methyl group, ethyl
group, aromatic group, acetate group (e.g. --OCOCH.sub.3), a
carboxylic group, a carboxylate (--COO.sup.-M.sup.+) with M=Na, K,
Li or a primary, secondary or tertiary amine providing the cationic
charge, an amide group, a sulfonic or a phosphonic acid group. It
should be noted that subsequent to polymerization, the acetate
group may then be converted into an alcohol group (--OH).
Accordingly the second monomer can include
2-acrylamido-2-methyl-1-propanesulfonic acid having the following
structure:
##STR00008##
[0025] In addition, one may utilize acrylamide having the following
structure:
##STR00009##
[0026] Furthermore, one may utilize a vinyl phosphonate, such as
vinylphosphonic acid having the following structure:
##STR00010##
[0027] Upon polymerization and the simultaneous decarboxylation and
introduction of amide functionality discussed herein, one may then
form the following polymer structure:
##STR00011##
[0028] In the above repeat unit a is present in the range of 1-99
wt. %, repeat unit b is present in the range of 1-99 wt. % and
repeat unit c is present in the range of 0-50 wt. % and repeat
units a, b and c are present at a total of 100 wt. %, wherein
R.sub.4, R.sub.5 or R.sub.6 can individually be selected from an
--OH group (to represent carboxylic acid functionality),
O.sup.-M.sup.+ (to represent a carboxylate) where M=Na, K, Li or a
primary, secondary or tertiary amine providing the cationic charge
and at least of portion of R.sub.4, R.sub.5 or R.sub.6 is
--NHR.sub.7 (which provides the amide linkage from the amidation
reaction) wherein R.sub.7 in --NHR.sub.4 is independently selected
from the group consisting of:
[0029] (1) an alkyl chain of up to and including 20 carbon atoms,
to provide for example: --(CH.sub.2).sub.19CH.sub.3, said alkyl
chain optionally including a sulfonic acid group, an alcohol group,
amine group or carboxylic acid group to provide, for example:
--CH.sub.2CH.sub.2--SO.sub.3H or --CH.sub.2CH.sub.2OH or
--CH.sub.2CH.sub.2NH.sub.2 or --CH.sub.2CH.sub.2COOH; or
[0030] (2) an L-cysteine derivative comprising:
##STR00012##
or
[0031] (3) an aromatic group to provide --NHAr; or
[0032] (4) alkyl polyether functionality as in polyethylene oxide
--(CH.sub.2CH.sub.2O).sub.n--CH.sub.2CH.sub.2OH or polypropylene
oxide --(CH.sub.2CH(CH.sub.3)O).sub.n--CH.sub.2CH(CH.sub.3)OH where
n has a value of up to and including 50 repeat units for the
indicated ethylene oxide (EO) or propylene oxide (PO) repeating
unit or an ethylene oxide/propylene oxide copolymer repeating unit
structure, as in
--(CH.sub.2CH.sub.2O).sub.x--(CH.sub.2CH(CH.sub.3)O).sub.y--CH.sub.2CH(CH-
.sub.3)--OH where x and y in combination provide up to and
including 50 repeating units; or
[0033] (5) polysiloxane functionality as in
##STR00013##
[0034] In the above, Y.sub.1 may be an alkyl group such as a methyl
group (--CH.sub.3) or ethyl group (--CH.sub.2CH.sub.3) or phenyl
group and Z is an optional linking functionality which may include
an ethyl group such as --CH.sub.2CH.sub.2-- or a propyl group such
as --CH.sub.2CH.sub.2CH.sub.2-- and the value of m is up to and
including 20.
[0035] On the issue of decarboxylation, it should therefore be
noted that decarboxylation herein proceeds generally as follows,
and with reference to the partially neutralized polyitaconic acid
portion of the polymer structure above, it appears to occur on the
carboxylic acid group attached to the main chain such that
repeating unit "a" as shown below is decarboxylated to provide
repeating unit "b":
##STR00014##
[0036] Amidation of the carboxylic acid group by treatment of the
polymerized and partially neutralized polyitaconic acid by
treatment with R.sub.7NH.sub.2, with R.sub.7 as defined above, may
be illustrated as follows:
##STR00015##
[0037] The simultaneous decarboxylation and introduction of amide
functionality may now be generally written as follows:
##STR00016##
[0038] In the above, at least a portion of R.sub.4, R.sub.5 or
R.sub.6 comprises --NHR.sub.7. Accordingly, the polymer so produced
may have any one or more of the following structures:
##STR00017##
[0039] As noted above, the value of "a" in the above terpolymer
structure may be from 1-99 wt. %, the value of "b" may be in the
range of 1-99 wt. % (which reflects the relative amount of
decarboxylation) and the value of "c" may be in the range of 0 to
50 wt. %, which then can be selected to add up to 100 wt. %.
Preferably, the value of "b" may fall in the range of 5-80 wt. % or
10-75 wt. %. As noted, the presence of repeat unit "c" is optional.
Preferably, when repeat unit "a" is present at a level of 5-80 wt.
%, repeat unit "b" is present at a level of 5-80 wt. % and repeat
unit "c" is present at a level of 0-35 wt. %. More preferably, when
repeat unit "a" is present at a value of 5-30 wt. %, repeat unit
"b" is present at a level of 60-80 wt. % and repeat unit "c" is
present at a level of 0-25 wt. %. In addition, R.sub.1, R.sub.2 and
R.sub.3 are as defined above and as noted, in view of the
introduction of amide functionality at the time of decarboxylation,
at least a portion of R.sub.4, R.sub.5 and R.sub.6 now comprises
--NHR.sub.4 where R.sub.4 is defined above. Preferably, the polymer
formed herein is such that the number average molecular weight (Mn)
has a value of 500 to 10,000 or a weight average molecular weight
(Mw) of 800 to 100,000. Furthermore, the decarboxylation and
amidation reactions herein are such that they may preferably be
conducted in the absence of any catalysis.
[0040] In addition, the polymers herein may be produced to have a
desired level of tacticity with respect to analysis of triad
structure by NMR techniques. For example, the polymers herein may
be formed with the presence of syndiotactic triads, at a level of
greater than 58.0%. For example, the level of syndiotactic triads
as determined by NMR techniques, such as C.sup.13 NMR, may be
formed at the level of greater than 58.0% to 75.0%, including all
values therein, in 1.0% increments.
[0041] With respect to the various polymerizations noted above, it
is contemplated herein that the polymerizations may be suitable for
a continuous polymerization process (i.e. a polymerization process
that runs continuously and continuously provides polymeric
material).
[0042] Furthermore, with respect to the feature that at least a
portion of R.sub.4, R.sub.5 or R.sub.6 comprises --NHR.sub.7, which
then defines amide functionality wherein --NHR.sub.7 is itself
connected to carbonyl functionality, the level of such amide
substitution is characterized herein as a weight ratio
corresponding to the amount of covalently bound --NHR.sub.7 over
the initial amount of unsubstituted polymer. In addition the
substitution yield is determined by the weight ratio of the amount
of covalently bound --NHR.sub.7 over the amount of amine (i.e.
NH.sub.2R.sub.7) initially added at the start of the reaction. The
amide substitution level and the amide substitution yield may be
determined with a gel permeation chromatograph by quantifying the
amount of free amine and the amount of polymer with the following
equations:
Amide Substition Level = Weight Amount Of Free Amine Introduced
Initial Weight of Unsubstituted Polymer ##EQU00001## Amide
Substition Yield = 1 - Weight Amount of Free Amine Remaining Weight
Amount of Free Amine Introduced ##EQU00001.2##
[0043] Accordingly, the amide substitution yield herein can fall in
the range of 25% to 99%, preferably in the range of 50% to 99%,
more preferably in the range of 75% to 99%, and even more
preferably in the range of greater than or equal to 90% up to
99%.
EXAMPLES
Example 1
[0044] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=2022 g/mole Mw=4158 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.5
and a moisture content of 16.9% was used as starting polymer. 48.18
gr of this polymer was dissolved in 60 gr of water at 60.degree. C.
in a 250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 6.59 grams of taurine was added. The
solution was heated to 100.degree. C. for 23 hours. The resulting
polymer had a yellow/orange color, and remained in solution upon
cooling. Resulting polymer solution had 61.3% moisture content, a
pH of 7.7. Acid number determination showed 40 mole %
decarboxylation. Amide substitution yield was determined to be 98%.
Scale inhibition testing resulted in a transmittance at 2 ml of
76%, at 3.1 ml of 50% and at 4 ml of 38%.
Example 2
[0045] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=2022 g/mole Mw=4158 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.5
and a moisture content of 16.9% was used as starting polymer. 48.18
gr of this polymer was dissolved in a mixture of 60 gr of water and
10.5 g of 50 wt % sodium hydroxide solution at 60.degree. C. in a
250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 6.59 grams of taurine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had a yellow/orange color, and remained in solution upon
cooling. Resulting polymer solution had 61.3% moisture content, a
pH of 10.8. Acid number determination showed 26 mole %
decarboxylation. Amide substitution yield was determined to be 97%.
Scale inhibition testing resulted in a transmittance at 2 ml of
85%, at 3.1 ml of 54% and at 4 ml of 35%.
Example 3
[0046] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=2022 g/mole Mw=4158 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.5
and a moisture content of 16.9% was used as starting polymer. 48.20
gr of this polymer was dissolved in 60 gr of water at 60.degree. C.
in a 250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 3.24 grams of ethanolamine was added.
The solution was heated to 100.degree. C. for 24 hours. The
resulting polymer had an orange color, and remained in solution
upon cooling. Resulting polymer solution had 69.5% moisture
content, a pH of 8.90. Acid number determination showed 30 mole %
decarboxylation. Amide substitution yield was determined to be 85%.
Scale inhibition testing resulted in a transmittance at 2 ml of
79%, at 3.1 ml of 47% and at 4 ml of 26%.
Example 4
[0047] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=2022 g/mole Mw=4158 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.5
and a moisture content of 16.9% was used as starting polymer. 48.19
gr of this polymer was dissolved in a mixture of 62 gr of water and
10.55 gr of 50 wt % sodium hydroxide solution at 60.degree. C. in a
250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 3.21 grams of ethanolamine was added.
The solution was heated to 100.degree. C. for 24 hours. The
resulting polymer had an orange color, and remained in solution
upon cooling. Resulting polymer solution had 61.9% moisture
content, a pH of 11.2. Acid number determination showed 21 mole %
decarboxylation. Amide substitution yield was determined to be 88%.
Scale inhibition testing resulted in a transmittance at 2 ml of
89%, at 3.1 ml of 54% and at 4m1 of 18%.
Example 5
[0048] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=2022 g/mole Mw=4158 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.5
and a moisture content of 16.9% was used as starting polymer. 48.20
gr of this polymer was dissolved in 60 gr of water at 60.degree. C.
in a 250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 3.85 grams of butylamine was added. The
solution was heated to 90-95.degree. C. for 24 hours. The resulting
polymer had an orange color, and remained in solution upon cooling.
Resulting polymer solution had 63.3% moisture content, a pH of 9.2.
Acid number determination showed 30 mole % decarboxylation. Amide
substitution yield was determined to be 97%. Scale inhibition
testing resulted in a transmittance at 2 ml of 82%, at 3.1 ml of
55% and at 4 ml of 27%.
Example 6
[0049] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=2022 g/mole Mw=4158 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.5
and a moisture content of 16.9% was used as starting polymer. 48.19
gr of this polymer was dissolved in 60 gr of water at 60.degree. C.
in a 250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 6.39 grams of L-cysteine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had a dark red/orange color, and remained in solution upon
cooling. Resulting polymer solution had 68.2% moisture content, a
pH of 7.3. Acid number determination showed 28 mole %
decarboxylation. Amide substitution yield was determined to be 96%.
Scale inhibition testing resulted in a transmittance at 2 ml of
74%, at 3.1 ml of 39% and at 4 ml of 16%.
Example 7
[0050] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=2022 g/mole Mw=4158 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.5
and a moisture content of 16.9% was used as starting polymer. 48.19
gr of this polymer was dissolved in a mixture of 60 gr of water and
21.15 gr of 50 wt % sodium hydroxide solution at 60.degree. C. in a
250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 6.39 grams of L-cysteine was added. The
solution was heated to 100.degree. C. for 23 hours. The resulting
polymer had a bright yellow color, and split into two layers upon
cooling. Resulting polymer solution had 64.4% moisture content, a
pH of 11.3. Acid number determination showed 0 mole %
decarboxylation. Amide substitution yield was determined to be
>99%. Scale inhibition testing resulted in a transmittance at 2
ml of 64%, at 3.1 ml of 36% and at 4 ml of 17%.
Example 8
[0051] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=2022 g/mole Mw=4158 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.5
and a moisture content of 16.9% was used as starting polymer. 48.19
gr of this polymer was dissolved in a mixture of 60 gr of water and
10.55 gr of 50 wt % sodium hydroxide solution at 60.degree. C. in a
250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 6.39 grams of L-cysteine was added. The
solution was heated to 100.degree. C. for 22 hours. The resulting
polymer had an orange/yellow color, and split into two layers upon
cooling. Resulting polymer solution had 68.2% moisture content, a
pH of 10.4. Acid number determination showed 17 mole %
decarboxylation. Amide substitution yield was determined to be 79%.
Scale inhibition testing resulted in a transmittance at 2 ml of
83.4%, at 3.1 ml of 43% and at 4 ml of 16%.
Example 9
[0052] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=2022 g/mole Mw=4158 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.5
and a moisture content of 16.9% was used as starting polymer. 48.19
gr of this polymer was dissolved in a mixture of 60 gr of water and
21.05 gr of 50 wt % sodium hydroxide solution at 60.degree. C. in a
250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 5.27 grams of Jeffamine.RTM. M1000 was
added. The solution was heated to 100.degree. C. for 23 hours. The
resulting polymer had a yellow color, and split into two layers
upon cooling. Resulting polymer solution had 59% moisture content,
a pH of 11.7. Acid number determination showed 12 mole %
decarboxylation. Amide substitution yield was determined to be 71%.
Scale inhibition testing resulted in a transmittance at 2 ml of
59%, at 3.1 ml of 31% and at 4 ml of 12%.
Example 10
[0053] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=2022 g/mole Mw=4158 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.5
and a moisture content of 16.9% was used as starting polymer. 48.20
gr of this polymer was dissolved in a mixture of 60 gr of water and
21.13 gr of 50 wt % sodium hydroxide solution at 60.degree. C. in a
250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 5.25 grams of Jeffamine.RTM. D2000 was
added. The solution was heated to 100.degree. C. for 23 hours. The
resulting polymer had a yellow color, and split into two layers
upon cooling. Resulting polymer solution had 60% moisture content,
a pH of 11.6. Acid number determination showed 32 mole %
decarboxylation. Amide substitution yield was determined to be 83%.
Scale inhibition testing resulted in a transmittance at 2 ml of
58%, at 3.1 ml of 31% and at 4 ml of 13%.
Example 11
[0054] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=1501 g/mole Mw=6293 g/mole,
monomer to polymer conversion greater than 94 wt. %, a pH of 3.9
and a moisture content of 10.8% was used as starting polymer. 42.95
gr of this polymer was dissolved in 60 gr of water at 60.degree. C.
in a 250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 6.63 grams of taurine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had a yellow/orange color, and remained in solution upon
cooling. Resulting polymer solution had 62.8% moisture content, a
pH of 4.7. Acid number determination showed 34 mole %
decarboxylation. Amide substitution yield was determined to be 74%.
Scale inhibition testing resulted in a transmittance at 2 ml of
91%, at 3.1 ml of 79% and at 4 ml of 67%.
Example 12
[0055] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 1K.TM., with a Mn=889 g/mole Mw=1403 g/mole,
monomer to polymer conversion greater than 8 wt. %, a pH of 5.1 and
a moisture content of 11.5% was used as starting polymer. 51.29 gr
of this polymer was dissolved in a mixture of 60 gr of water and
21.04 gr of 50 wt % sodium hydroxide solution at 60.degree. C. in a
250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 6.60 grams of taurine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had a yellow/orange color, and remained in solution upon
cooling. Resulting polymer solution had 56.8% moisture content, a
pH of 11.0. Acid number determination showed 27 mole %
decarboxylation. Amide substitution yield was determined to be 65%.
Scale inhibition testing resulted in a transmittance at 2 ml of
90%, at 3.1 ml of 53% and at 4 ml of 23%.
Example 13
[0056] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 1K.TM., with a Mn=1323 g/mole Mw=2298 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.0
and a moisture content of 17.3% was used as starting polymer. 48.20
gr of this polymer was dissolved in a mixture of 60 gr of water and
21.08 gr of 50 wt % sodium hydroxide solution at 60.degree. C. in a
250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 6.60 grams of taurine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had a yellow/orange color, and remained in solution upon
cooling. Resulting polymer solution had 59.6% moisture content, a
pH of 11.6. Acid number determination showed 24 mole %
decarboxylation. Amide substitution yield was determined to be 57%.
Scale inhibition testing resulted in a transmittance at 2 ml of
87%, at 3.1 ml of 43% and at 4 ml of 26%.
Example 14
[0057] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=2022 g/mole Mw=4158 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.5
and a moisture content of 16.9% was used as starting polymer. 48.20
gr of this polymer was dissolved in a mixture of 80 gr of water and
21.15 gr of 50 wt % sodium hydroxide solution at 60.degree. C. in a
250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 6.58 grams of taurine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had a yellow color, and remained in solution upon cooling.
Resulting polymer solution had 64.8% moisture content, a pH of
11.4. Acid number determination showed 25 mole % decarboxylation.
Amide substitution yield was determined to be 27%. Scale inhibition
testing resulted in a transmittance at 2 ml of 86%, at 3.1 ml of
38% and at 4 ml of 21%.
Example 15
[0058] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=2022 g/mole Mw=4158 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.5
and a moisture content of 16.9% was used as starting polymer. 48.20
gr of this polymer was dissolved in a mixture of 80 gr of water and
21.15 gr of 50 wt % sodium hydroxide solution at 60.degree. C. in a
250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 6.58 grams of taurine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had a yellow color, and remained in solution upon cooling.
Resulting polymer solution had 64.8% moisture content, a pH of
11.4. Acid number determination showed 25 mole % decarboxylation.
Amide substitution yield was determined to be 27%. Scale inhibition
testing resulted in a transmittance at 2 ml of 86%, at 3.1 ml of
38% and at 4 ml of 21%.
Example 16
[0059] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 5K.TM., with a Mn=6817 g/mole Mw=21195 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.4
and a moisture content of 16.4% was used as starting polymer. 48.20
gr of this polymer was dissolved in a mixture of 60 gr of water and
29.55 gr of 50 wt % potassium hydroxide solution at 60.degree. C.
in a 250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 6.59 grams of taurine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had an orange/yellow color, and remained in solution upon
cooling. Resulting polymer solution had 62.0% moisture content, a
pH of 11.5. Acid number determination showed 16 mole %
decarboxylation. Amide substitution yield was determined to be 68%.
Scale inhibition testing resulted in a transmittance at 2 ml of
88%, at 3.1 ml of 49% and at 4 ml of 17%.
Example 17
[0060] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 10K.TM., with a Mn=11271 g/mole Mw=59698 g/mole,
monomer to polymer conversion greater than 89 wt. %, a pH of 5.1
and a moisture content of 14.0% was used as starting polymer. 48.20
gr of this polymer was dissolved in a mixture of 70 gr of water and
29.60 gr of 50 wt % potassium hydroxide solution at 60.degree. C.
in a 250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 6.60 grams of taurine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had a dark orange color, and remained in solution upon
cooling. Resulting polymer solution had 63.0% moisture content, a
pH of 11.3. Acid number determination showed 15 mole %
decarboxylation. Amide substitution yield was determined to be 84%.
Scale inhibition testing resulted in a transmittance at 2 ml of
85%, at 3.1 ml of 45% and at 4 ml of 16%.
Example 18
[0061] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 1K.TM., with a Mn=889 g/mole Mw=1404 g/mole,
monomer to polymer conversion greater than 8.0 wt. %, a pH of 5.1
and a moisture content of 11.5% was used as starting polymer. 48.18
gr of this polymer was dissolved in 60 gr of water at 60.degree. C.
in a 250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 6.60 grams of taurine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had a bright yellow color, and remained in solution upon
cooling. Resulting polymer solution had 59.7% moisture content, a
pH of 6.1. Acid number determination showed 35 mole %
decarboxylation. Amide substitution yield was determined to be 95%.
Scale inhibition testing resulted in a transmittance at 2 ml of
73%, at 3.1 ml of 43% and at 4 ml of 24%.
Example 19
[0062] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 1K.TM., with a Mn=1324 g/mole Mw=2298 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.0
and a moisture content of 17.3% was used as starting polymer. 48.16
gr of this polymer was dissolved in 60 gr of water at 60.degree. C.
in a 250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 6.59 grams of taurine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had a bright yellow color, and remained in solution upon
cooling. Resulting polymer solution had 62.3% moisture content, a
pH of 6.5. Acid number determination showed 35 mole %
decarboxylation. Amide substitution yield was determined to be 90%.
Scale inhibition testing resulted in a transmittance at 2 ml of
77%, at 3.1 ml of 52% and at 4 ml of 41%.
Example 20
[0063] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP SK.TM., with a Mn=6817 g/mole Mw=21195 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.4
and a moisture content of 16.4% was used as starting polymer. 48.19
gr of this polymer was dissolved in 60 gr of water at 60.degree. C.
in a 250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 6.60 grams of taurine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had a bright orange color, and remained in solution upon
cooling. Resulting polymer solution had 63.5% moisture content, a
pH of 6.9. Acid number determination showed 36 mole %
decarboxylation. Amide substitution yield was determined to be 88%.
Scale inhibition testing resulted in a transmittance at 2 ml of
80%, at 3.1 ml of 58% and at 4 ml of 47%.
Example 21
[0064] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 10K.TM., with a Mn=11271 g/mole Mw=59698 g/mole,
monomer to polymer conversion greater than 89 wt. %, a pH of 5.1
and a moisture content of 14.0% was used as starting polymer. 48.19
gr of this polymer was dissolved in 60 gr of water at 60.degree. C.
in a 250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 6.60 grams of taurine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had a dark brown color, and remained in solution upon
cooling. Resulting polymer solution had 63.5% moisture content, a
pH of 6.9. Acid number determination showed 36 mole %
decarboxylation. Amide substitution yield was determined to be 91%.
Scale inhibition testing resulted in a transmittance at 2 ml of
78%, at 3.1 ml of 59% and at 4 ml of 46%.
Example 22
[0065] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=2022 g/mole Mw=4158 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.5
and a moisture content of 16.9% was used as starting polymer. 48.17
gr of this polymer was dissolved in a mixture of 62 gr of water and
10.49 gr of 50 wt % sodium hydroxide solution at 60.degree. C. in a
250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 6.59 grams of taurine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had an orange color, and remained in solution upon cooling.
Resulting polymer solution had 64.3% moisture content, a pH of
10.6. Acid number determination showed 28 mole decarboxylation.
Amide substitution yield was determined to be 96%. Scale inhibition
testing resulted in a transmittance at 2 ml of 65%, at 3.1 ml of
41% and at 4 ml of 19%.
Example 23
[0066] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=2022 g/mole Mw=4158 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.5
and a moisture content of 16.9% was used as starting polymer. 48.18
gr of this polymer was dissolved in a mixture of 60 gr of water and
14.76 gr of 50 wt % potassium hydroxide solution at 60.degree. C.
in a 250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 6.58 grams of taurine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had an orange color, and remained in solution upon cooling.
Resulting polymer solution had 61.2% moisture content, a pH of
10.5. Acid number determination showed 27 mole % decarboxylation.
Amide substitution yield was determined to be 98%. Scale inhibition
testing resulted in a transmittance at 2 ml of 80%, at 3.1 ml of
52% and at 4 ml of 35%.
Example 24
[0067] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=2022 g/mole Mw=4158 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.5
and a moisture content of 16.9% was used as starting polymer. 48.19
gr of this polymer was dissolved in a mixture of 60 gr of water and
21.05 gr of 50 wt % sodium hydroxide solution at 60.degree. C. in a
250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 26.37 grams of taurine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had a light orange color, and remained in solution upon
cooling. Resulting polymer solution had 55.6% moisture content, a
pH of 10.5. Acid number determination showed 4 mole %
decarboxylation. Amide substitution yield was determined to be
49.8%. Scale inhibition testing resulted in a transmittance at 2 ml
of 79%, at 3.1 ml of 53% and at 4 ml of 42%.
Example 25
[0068] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=2022 g/mole Mw=4158 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.5
and a moisture content of 16.9% was used as starting polymer. 48.18
gr of this polymer was dissolved in 60 gr of water at 60.degree. C.
in a 250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 26.35 grams of taurine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had a light orange color, and remained in solution upon
cooling. Resulting polymer solution had 55.6% moisture content, a
pH of 7.3. Acid number determination showed 7 mole %
decarboxylation. Amide substitution yield was determined to be 65%.
Scale inhibition testing resulted in a transmittance at 2 ml of
75%, at 3.1 ml of 53% and at 4 ml of 44%.
Example 26
[0069] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=2022 g/mole Mw=4158 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.5
and a moisture content of 16.9% was used as starting polymer. 48.20
gr of this polymer was dissolved in 60 gr of water at 60.degree. C.
in a 250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 13.19 grams of taurine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had an orange color, and remained in solution upon cooling.
Resulting polymer solution had 59.8% moisture content, a pH of 7.9.
Acid number determination showed 32 mole % decarboxylation. Amide
substitution yield was determined to be 75%. Scale inhibition
testing resulted in a transmittance at 2 ml of 80%, at 3.1 ml of
60% and at 4 ml of 53%.
Example 27
[0070] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. DSP 2K.TM., with a Mn=2022 g/mole Mw=4158 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 5.5
and a moisture content of 16.9% was used as starting polymer. 48.19
gr of this polymer was dissolved in 60 gr of water at 60.degree. C.
in a 250 ml round bottom flask with magnetic stirring and a reflux
condenser. To this solution 19.77 grams of taurine was added. The
solution was heated to 100.degree. C. for 24 hours. The resulting
polymer had an orange color, and remained in solution upon cooling.
Resulting polymer solution had 57.1% moisture content, a pH of 7.5.
Acid number determination showed 28 mole % decarboxylation. Amide
substitution yield was determined to be 44%. Scale inhibition
testing resulted in a transmittance at 2 ml of 78%, at 3.1 ml of
56% and at 4 ml of 47%.
Example 28
[0071] A sample of commercial poly(sodium itaconate), tradename
Itaconix.RTM. XDP.TM. 820, with a Mn=2483 g/mole Mw=5777 g/mole,
monomer to polymer conversion greater than 98 wt. %, a pH of 6.1
and a moisture content of 60.5% was used as starting polymer. 94.81
gr of this polymer solution was warmed to 60.degree. C. in a 250 ml
round bottom flask with magnetic stirring and a reflux condenser.
To this solution 8.58 grams of taurine was added. The solution was
heated to 100.degree. C. for 24 hours. The resulting polymer had an
orange/brown color, and remained in solution upon cooling.
Resulting polymer solution had 53.4% moisture content, a pH of 7.5.
Acid number determination showed 57 mole % decarboxylation. Amide
substitution yield was determined to be 67%. Scale inhibition
testing resulted in a transmittance at 2 ml of 80%, at 3.1 ml of
55% and at 4 ml of 46%.
Determination of Decarboxylation Levels
[0072] A 10 gr of a polymer solution at 15 wt. % solid content is
prepared by diluting the polymer solution with reverse osmosis (RO)
water. Accurate moisture content of this solution is recorded using
a moisture analyzer scale. In a plastic beaker with a lid mix 5.0 g
of the 15 wt. % polymer solution previously made, one adds 7.5 g of
1N HCl, and 50.0 g RO water. A mixing bar is placed in the beaker
and the sample is placed on a stir plate. A pH probe is calibrated
with standards at pH=1.00 and pH=13.00. A 20 mL syringe is filled
with 1M NaOH and placed on an automatic syringe pump just over the
mixing solution on the stir plate. A data logger is used to record
pH as a function of time with a recording every second for 1500
seconds. Data recording and sodium hydroxide addition at the rate
of 50 ml/hr through the automatic syringe pump are started at the
same time. When the pH reaches about 12 the pump is stopped as well
as the data collection. The decarboxylation is reported as one (1)
minus the number of acid functions identified at pH greater than 7,
divided by the total number of acid function in the starting
polymer sample (assuming 2 acids per repeating unit of itaconic
acid), and expressed as a %.
[0073] Given that polyitaconic acid have two carboxylic acid groups
per repeat unit, the amount of decarboxylation may therefore
theoretically be 200 mole % (i.e. 200 mole % carbon dioxide may be
evolved per molar equivalent of itaconic acid in the polymer). In
the present disclosure the level of decarboxylation is preferably
above 30 mole % in the range of 40 mole % to 150 mole % of carbon
dioxide evolved per molar equivalent of itaconic acid in the
polymer.
Determination of pH for All Examples
[0074] All pHs are reported in solutions at 10 wt % in RO water at
room temperature. The pH probe is a Tris-Compatible flat sensor.
The pH meter is calibrated using pH4 and pH=7 standard solutions
prior to any measurement reading.
Molecular Weight Determination
[0075] Gel Permeation Chromatography (GPC) was used to determine
molecular weights and amide substitution yields. The GPC is first
equilibrated with the eluent (1.67% sodium nitrate in HPLC-grade
water) through three TOSOH Bioscience 08026 GPC columns for
approximately one hour. A refractive index detector (RID) is used
to measure signal concentration. The RID is purged for 20 minutes
before sample analysis is started. The following instrument
conditions are used: Eluent: 1.67 wt % sodium nitrate in HPLC-grade
water with inline degasser; Flow Rate: 1.0 mL/min; Run Time: 45
min; Injection volume: 100 .mu.L Draw/Eject Speed: 200 .mu.L/min;
RID Optics Temperature: 40.degree. C.; Automatic Purge: 1 min;
Column Temperature: 35.degree. C.
[0076] A 1 wt. % polymer solution is prepared using the GPC eluent
solution as solvent. This solution is filtered with a 0.2 .mu.M
syringe-tip filter into a 2 mL HPLC vial which is then crimped
closed. The vial is placed into the GPC autosampler and the
chromatographic run is initiated. Molecular weight calibration was
done using 6 polyacrylic acid standards with molecular weights
ranging from 1000 g/mole to 1,360,000 g/mole, and with itaconic
acid (monomer molecular weights 130). The 7 standards are used to
create a 3rd order polynomial correlation between peak elution time
and molecular weights. Each unknown sample is evaluated using this
calibration function.
[0077] Conversion was calculated by the relative area of the
residual monomer peak (with the longest elution time) over the
total (polymer+monomer) area. Conversion is expressed as a weight
percent.
Scale Inhibition Measurement
[0078] Scale inhibition and dispersant properties are determined by
a calcium titration method while measuring turbidity with a
transmittance probe. 0.06 grams of sodium carbonate, 0.04 grams of
polymer sample (dry basis), and 99.9 grams of RO water were mixed
together. 14 grams of the previous solution was titrated with a
calcium chloride solution at an active concentration of 2 wt % at
10 ml per hour over 10 minutes of time at room temperature. The
transmittance at 2 ml, 3.1 ml and at 4 ml is noted to reflect the
dispersion efficacy of the polymer.
[0079] This titration method generates in increasing amount of
calcium carbonate that can be effectively dispersed or inhibited
from its formation by the polymeric dispersant/scale inhibitor. A
relatively high transmittance value of the solution at 2 ml and 3.1
ml reflect a relatively high scale inhibition, while a relatively
high transmittance at 4 ml reflects the dispersing capability of
the polymer samples.
[0080] The scale inhibition that may be achieved with the partially
decarboxylated and amide functionalized polymers herein is
optimized where the level of polymer in solution subject to scaling
may be in the range of 1-50 ppm. In addition, for preferred
anti-scaling performance, the level of decarboxylation is
preferably in the range of 40 mole % to 150 mole % of carbon
dioxide per molar equivalent of itaconic acid and at a number
average molecular weight preferably in the range of 500 to 4000
g/mole.
[0081] Accordingly, the partially decarboxylated and amide
functionalized polymers herein are remarkably suitable for
prevention of scaling (ability to prevent unwanted material from
collection on a solid surface). Accordingly disclosed herein is a
method of adding to a given aqueous system an amount of the
partially neutralized and partially decarboxylated polymers herein
which is sufficient to complex polyvalent metal ions in the aqueous
system and prevent deposit formation in aqueous media. The
polyvalent metal ions may therefore include Ca.sup.+2, Ba.sup.+2,
Cr.sup.+2, Cr.sup.+3, Cu.sup.+2, Fe.sup.+2, Fe.sup.+3, Pb.sup.+2,
Mg.sup.+2, Mn.sup.+2, Mn.sup.+3, Hg.sup.+2, Sn.sup.+2, Sn.sup.+4,
Sr.sup.+2, Zn.sup.+3. Preferably the complexation herein is
directed at complex polyvalent ions of Ca.sup.+2, Mg.sup.+2 and
Ba.sup.+2 and Sr.sup.+2. Such metals may therefore be present as
e.g., metal carbonates (CO.sub.3.sup.2-), metal sulfates
(SO.sub.4.sup.2-), metal sulfites (SO.sub.3.sup.2-), or metal
thiosulfites (S.sub.2O.sub.3.sup.2-).
[0082] Applications of the above for the prevention of scaling may
therefore apply to and include, but not be limited to, pipes,
boilers, oil and gas exploration (downhole drilling systems), water
cooling systems, water purification systems (e.g., reverse osmosis
systems), distillation systems, dishwasher systems and laundry
systems.
Dispersion Properties
[0083] The partially decarboxylated and amide functionalized
polymers herein also provide a material with, amongst other
features, enhanced dispersion properties of inorganic minerals in
solution. Inorganic minerals may be understood as including: (1)
inorganic carbonates (e.g. inorganic compounds containing the
anionic carbonate group [CO.sub.3].sup.2- such as CaCO.sub.3 or
MgCO.sub.3); (2) inorganic oxides including simple oxides,
hydroxides and multiple oxides (e.g., TiO.sub.2, Al.sub.2O.sub.3,
Fe.sub.2O3); (3) inorganic sulfates (e.g. inorganic compounds
containing the sulfate anion SO.sub.4.sup.2- an example of which is
CaSO.sub.4); (4) inorganic phosphates (e.g. inorganic compounds
containing the anion PO.sub.4.sup.3- such as
Ca.sub.5(PO.sub.4).sub.3(OH); and (5) silicates (inorganic
compounds that contain the [SiO4].sup.4- anion).
[0084] In particular, it can be noted that amidation herein via the
use of taurine (H.sub.2N--CH.sub.2CH.sub.2--SO.sub.3H) one
incorporates a NH--R.sub.4 functionality, i.e.
--NH--CH.sub.2CH.sub.2--SO.sub.3H, which thereby incorporates a
sulfonic acid into the polymer, which then provide a polymer with
improved solubility in hard water (water with equivalent calcium
carbonate greater or equal to 100 parts per million). In addition,
the polymers herein can enhance the compatibility of ingredients in
inks, carbon dispersions or iron oxide dispersions.
Moisture Content
[0085] A moisture scale analyzer was employed. It records weight as
function of time, while maintaining the sample at 110.degree. C.
using an infrared heater. When a constant weight is recorded for 30
seconds, the test is completed and the weight recorded as a percent
decrease from the initial weight. All moisture contents are
expressed as weight percent.
* * * * *